Mast for a wind turbine
The invention relates to a mast ( 10 ) for a wind turbine, which mast tapers towards the top and comprises at least two superposed annular mast sections ( 12, 14, 16, 18, 20 ). Every annular mast section consists of a plurality of prefabricated wall parts (A, B, C, D, E, F), wherein at least a part of which has a curved section, at least the curved sections of prefabricated wall parts in different annular mast sections having at least identical cross-section.
1. A mast for a wind turbine, the mast having a longitudinal length that tapers towards a top and comprises at least two annular mast sections vertically arranged on top of each other,
wherein each of said at least two annular mast sections tapers from a bottom to a top and includes a plurality of prefabricatable wall parts formed substantially of concrete, at least some of which have a curved section,
characterized in that at least some of the curved sections of prefabricatable wall parts in different annular mast sections have cross-sections perpendicular to the longitudinal length of the same size and shape along their length from being formed in a single common base mold.
2. The mast according to claim 1 , wherein the curved sections have an arc-shaped cross-section.
3. The mast according to claim 1 , wherein the annular mast sections have a polygon shaped cross-section with arc-shaped corners.
4. The mast according to claim 3 , wherein the polygon shaped cross-sections have between three and six arc-shaped corners.
5. The mast according to claim 1 , wherein the annular mast sections include alternately arranged curved wall parts and plane wall parts wherein the curved wall parts in different annular mast sections are identical.
6. The mast according to claim 5 , wherein at least some of the plane wall parts are substantially trapezoidal.
7. The mast according to claim 6 , wherein the trapezoidal plane wall parts within each of the annular mast section are identical.
8. The mast according to claim 6 , wherein the trapezoidal plane wall parts are dimensioned so that abutting edges of trapezoidal wall parts of two adjacent annular mast sections have the same length.
9. The mast according to claim 5 , wherein two adjacent annular mast sections have abutting plane wall parts which meet along a common plane wall joint and abutting curved wall parts which meet along a common curved wall joint, wherein the plane wall joint is offset in a longitudinal direction from the curved wall joint.
10. The mast according to claim 5 , wherein the plane wall parts in a bottom annular mast section of the mast are either shorter or longer in longitudinal direction than the curved wall parts, the plane wall parts in a top mast section are correspondingly longer or shorter, respectively, than the curved wall parts, and the plane wall parts in an intermediate annular mast sections are of the same length as the curved wall parts.
11. The mast according to claim 1 , wherein at least some of the prefabricatable wall parts comprise a curved section and a substantially trapezoidal plane section.
12. A method for manufacturing a mast for a wind turbine, the mast having a longitudinal length that tapers towards a top and comprises at least two annular mast sections each tapering from a bottom to a top and vertically arranged on top of each other, the method comprising:
prefabricating a plurality of wall parts formed substantially from concrete for each of the at least two annular mast sections including molding with a single common base mold some wall parts for different annular mast sections having a curved section, wherein at least some of the prefabricated wall parts with curved sections of different annular mast sections have cross-sections perpendicular to the longitudinal length of the same size and shape along their length; and
assembling the annular mast sections from the prefabricated wall parts to form the mast.
13. A method according to claim 12 , wherein the curved sections have an arc-shaped cross-section.
14. A method according to claim 12 , wherein the annular mast sections have a polygon shaped cross-section with arc-shaped corners.
15. A method according to claim 14 , wherein the polygon has between three and six arc-shaped corners.
16. A method according to claim 12 , wherein each of the annular mast sections is constructed of alternately arranged curved wall parts and plane wall parts, wherein the curved wall parts in different annular mast sections are identical.
17. A method according to claim 16 , wherein at least some of the plane wall parts are substantially trapezoidal.
18. A method according to claim 17 , wherein the trapezoidal plane wall parts within each of the annular mast section are identical.
19. A method according to claim 12 , wherein at least some of the wall parts are manufactured by using variable molds so that wall parts of different sizes can be manufactured with the same variable mold.
20. A method according to claim 19 , wherein the wall parts that are manufactured with the same variable mold include planar-shape wall parts.
21. A method according to claim 19 , wherein a variable mold with an unvarying section for forming a curved wall section and a variable section for forming a plane wall part section of different shape or size is used.